As suggested by @vk.khurava it looks like your post is creating the action and for the right fixlet. Do you have access to the machine you are issuing this to?
What is the actionscript for your fixlet, and what client version are you running? Is there 1 or more user logged into the system?
If the action uses
restart then I believe that will present a UI to a logged in user and they have to invoke the restart, it won’t automatically perform the restart… If you use
restart follow by a number, eg
restart 60 that would trigger the UI to a logged in user but automatically invoke the restart after the number of seconds you specified.